船舶专业英语
1 The Naval Architect 1 2 Definitions, Principal Dimensions 5 3 Merchant ship Types 12 4 Ship Design 18 5 General Arrangement 22 6 Ship Lines 27 7 Ship Equilibrium, Stability and Trim 31 8 Estimating Power Requirements 36 9 Ship Motions, Manoeuvrability 41 10 The Function of Ship Structural Components 44 11Structural Design, Ship Stresses 48 12Classification Societies 54 13 Shipyard, Organization, Layout 59 14 Planning, From Contract to Working Plans 62 15 Lines Plan and Fairing, Fabrication and Assembly 64 16 Launching and Outfitting 68 17 Sea Trials 70 18 Marine Engines 73
The Naval Architect Lesson One
The Naval Architect
A naval architect asked to design a ship may receive his
instructions in a form ranging from such simple requirements as ―an oil tanker to carry 100 000 tons deadweight at 15 knots‖ to a fully detailed specification of precisely planned requirements. He is usually
required to prepare a design for a vessel that must carry a certain weight of cargo (or number of passengers ) at a specified speed with particular reference to trade requirement;
high-density cargoes, such as machinery, require little hold capacity, while the reverse is true for low-density cargoes, such as grain.
Deadweight is defined as weight of cargo plus fuel and consumable stores, and lightweight as the weight of the hull, including machinery and equipment. The designer must choose dimensions such that the displacement of
the vessel is equal to the sum of the dead weight and the
lightweight tonnages. The fineness of the hull must be appropriate to the speed. The draft------which is governed by freeboard rules------enables the depth to be
determined to a first approximation.
After selecting tentative values of length, breadth, depth, draft, and displacement, the designer must achieve a weight balance. He must also select a moment balance because centres of gravity in both longitudinal and vertical directions must provide satisfactory trim and stability. Additionally, he must estimate the shaft horsepower
required for the specified speed; this determines the weight of machinery. The strength of the hull must be
adequate for the service intended, detailed scantlings (frame dimensions and plate thicknesses ) can be obtained from the rules of the
classification society. These scantings determine the requisite weight of hull steel.
The vessel should possess satisfactory steering characteristics, freedom from troublesome vibration, and should comply with the many varied requirements of international regulations. Possessing an attractive
appearance, the ship should have the minimum net register tonnage, the factor on which harbour and other dues
are based. (The gross tonnage represents the volume of all closed-in spaces above the inner bottom. The net
tonnage is the gross tonnage minus certain deductible spaces that do not produce revenue. Net tonnage can
therefore be regarded as a measure of the earning capacity of the ship, hence its use as a basis for harbour and docking charges. ) Passenger vessels must satisfy a standard of bulkhead subdivision that will ensure adequate
stability under specified conditions if the hull is pierced accidentally or through collision.
Compromise plays a considerable part in producing a satisfactory design. A naval architect must be a master of approximations. If the required design closely resembles that of a ship already built for which full information is available, the designer can calculate the effects of differences between this ship and the projected ship. If, however, this
information is not available, he must first produce coefficients based upon experience and, after
refining them, check the results by calculation. Training
There are four major requirements for a good naval architect. The first is a clear understanding of the fundamental principles of applied science, particularly those aspects of science that have direct application to ships------mathematics, physics, mechanics, fluid mechanics, materials, structural strength, stability, resistance, and propulsion. The second is a detailed knowledge of past and present practice in shipbuilding. The third is
personal experience of accepted methods in the design, construction, and operation of ships; and the fourth, and perhaps most important, is an aptitude for tackling new technical problems and of devising practical solutions.
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The Naval Architect
The professional training of naval architects differs widely in the various maritime countries. Unimany
universities and polytechnic schools; such academic training must be supplemented by practical experience in a
Trends in design shipyard.
The introduction of calculating machines and computers has facilitated the complex calculations required in
naval architecture and has also introduced new concepts in design. There are many combinations of length,
breadth, and draft that will give a required displacement. Electronic computers make it possible to prepare series
of designs for a vessel to operate in a particular service and to assess the economic returns to the shipowner for
each separate design. Such a procedure is best carried out as a joint exercise by owner and builder. As ships
increase in size and cost, such combined technical and economic studies can be expected to become more
common.
(From ―Encyclopedia Britannica‖, Vol. 16) Technical terms
1. naval architect 造船工程（设计）师 21. breadth 船宽
naval architecture造船（工程）学 22. freeboard 干舷 2. instruction 任务书、指导书 23. rule 规范 3. oil tanker 油轮 24. tentative 试用（暂行）的 4. deadweight 载重量 25. longitudinal direction 纵向 5. knot 节 26. vertical direction 垂向 6. specification 规格书，设计任务书 27. trim 纵倾 7. vessel 船舶 28. stability 稳性 8. cargo 货物 29. shaft horse power 轴马力 9. passenger 旅客 30. strength 强度 10. trade 贸易 31. service 航区、服务 11. machinery 机械、机器 32. scantling 结构（件）尺寸 12. hold capacity 舱容 33. frame 肋骨 13. consumable store 消耗物品 34. classification society 船级社 14. light weight 轻载重量、空船重量 35. steering 操舵、驾驶 15. hull 船体 36. vibration 振动 16. dimension 尺
船舶专业英语
